Apparatus for controlling management information of signals recording on disk recording medium

ABSTRACT

A recording apparatus records, in a recording medium, moving image data and management information, concerning the moving image data and generated in accordance with the recording operation of the moving image data. In accordance with a recording start instruction, the recording apparatus starts recording of the moving image data and records, in the recording medium, information indicating that the management information has not yet been recorded. In accordance with a recording stop instruction, the recording medium stops recording of the moving image data, generates and records the respective management information, and updates the information indicating the recording status of the management information. If a decrease in electric power is detected during recording of the moving image data, the recording apparatus stops recording of the moving image data, without updating the information indicating the recording status of the management information.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of application Ser. No. 11/100,851,filed Apr. 7, 2005 now U.S. Pat. No. 7,684,680; which is a divisional ofapplication Ser. No. 09/640,301, filed Aug. 16, 2000, which issued asU.S. Pat. No. 6,904,229 on Jun. 7, 2005, the entire disclosures of whichare hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus for recording signals suchas image signals on a disk recording medium and, more particularly, tocontrol of management information of recorded signals.

2. Related Background Art

Conventionally, a video tape recorder which records analog video signalson magnetic tapes is available as an image recording apparatus forrecording video signals on a recording medium. However, with rapidprogress of digital signal processing technologies, digitalrecording/playback apparatuses which record analog video signals onrecording medium by converting the signals into digital video signalsare becoming popular at present.

Such digital recording/playback apparatuses include a digital VTR, adigital video disk apparatus which records signals on solid-state diskor magnetooptical disk, and a solid-state memory video apparatus whichrecords signals in a solid-state memory such as a flash memory or anSRAM.

These digital recording/playback apparatuses load a video signalobtained by an image pickup device such as a CCD and convert the signalinto a digital signal by A/D conversion. The apparatuses reduce theinformation amount by compression-encoding this digital video signal. Inthis manner, these apparatuses can record a large amount of imageinformation in a small recording capacity.

Schemes used as this compression encoding are discrete cosine transform(to be referred to as DCT hereinafter) which is orthogonaltransformation having the highest compression efficiency, and avariable-length coding scheme. To perform compression encoding, a singleimage is first segmented into a plurality of blocks each having xhorizontal pixels and y vertical pixels, and DCT transform is performedfor each block A. DCT coefficient after the transform is divided by acertain divisor, and the remainder is rounded, thereby performingquantization. By using the characteristic that a quantized image isconcentrated in low-frequency components, the number of bits ofhigh-frequency components is reduced. In this way, the informationamount is greatly reduced.

The information amount can be further compressed by performingvariable-length encoding, e.g., Huffman coding, which assigns to thequantized data a code length corresponding to the occurrence frequencyof the data.

Furthermore, greater compression can be attained by combining interframepredictive encoding which calculates the difference between frames, byusing the characteristic that a motion image has a strong correlationbetween frames.

Of this type of recording/playback apparatuses, the capacities of diskmedia of disk apparatuses are rapidly increasing in recent years.Consequently, apparatuses which record and play not only audio signalsbut video signals in and from a disk medium for a long time have beenproposed. For example, a technique has been proposed which uses arecording format based on high-efficiency encoding such as MPEG using,e.g., DCT and variable-length encoding described above, and which canrealize a recording/playback apparatus which records video signals forone hour or more at data rates of about 4 Mbps and 10 Mbps. Furthermore,disk media themselves are being reliably decreased in size and increasedin capacity.

In an image recording apparatus which records video signals on a diskmedium by reducing the information amount by compressing the signals bycombining the aforementioned compression techniques, the informationamount varies in accordance with an image because variable-lengthencoding is used. Therefore, a rate control means for holding theinformation amount constant is used to uniformize the recording rate ofimages, thereby recording images in a predetermined recording mediacapacity within a predetermined time.

This rate control uniformizes the rate by writing compressed data havingvariations into a certain predetermined buffer and reading out the dataat a constant rate. That is, buffer control is performed such that ifthe data may exceed a predetermined value of the buffer, thequantization level described above is increased to raise the compressionratio; if the buffer does not satisfy the predetermined value, thequantization level is decreased to lower the compression ratio.

In constant bit rate recording (CBR recording), the recording rate isheld constant by giving priority to the target time of recording on arecording medium. Hence, if an input image moves fast or has a widecolor band, quantization becomes coarse to make the image nonuniformbetween frames. Therefore, an image recording apparatus which performsvariable bit rate recording (VBR recording) by attaching importance toimage quality has been proposed. This VBR recording performs encodinggiving priority to image quality by holding the quantization level ofrecording at a substantially constant value, while allowing fluctuationsof the recording rate.

A recording/playback apparatus like this uses management informationcalled Table of Contents (to be referred to as a TOC hereinafter) tocontrol video data recording and playback operations. When video dataobtained by image pickup is recorded on a recording medium, the TOCinformation is recorded in an area formed on the inner peripheral sideof the disk medium independently of an area for recording video data. Inplayback operation, the TOC information is read out from the disk mediumand held in an internal memory of the apparatus. On the basis of thisTOC information, the position of access to the disk medium and diverseoperations such as video data playback management are controlled.

Examples of operations managed using the TOC are an operation of linkingdata of one scene, which are discontinuously recorded on a recordingmedium, and continuously displaying back the data, an operation ofdeleting a scene once obtained by image pickup, and an operation ofrecording a scene newly obtained by image pickup in a free space formedby deletion.

In any of these operations, video data is recorded in an area (videorecording area) formed near the center in the radial direction of a diskmedium, and the TOC information is saved in an area (system informationmanagement area) formed inside the image recording area. Note that nodata can be recorded in the outer periphery of the disk.

Since the TOC is important information necessary to recording/playback,the reliability is improved by, e.g., recording the TOC a plurality oftimes in the system management area of a disk.

In conventional image pickup recording/playback apparatuses, the TOC isrecorded on a disk after video data is completely written in the medium.That is, after the recording end pointer (address) of video data on adisk is determined, various pieces of information including an endpointer and start pointer are recorded as the TOC information.

If, therefore, one recorded scene extends over a long time period, noTOC information may be recorded for long periods of time.

Also, a system using a disk medium can rapidly access data in the diskmedium, so recording or playback access to the disk medium is usuallyintermittently performed. Between this disk access operation and otheroperations, large differences are produced in consumption power such asmotor driving power, head driving power, and write laser power.

When a series of recording operations are performed with batterydriving, therefore, the battery supply voltage lowers with an abruptrise of the consumption power upon disk access. This sometimes makes therecording operations of the system impossible to perform.

Especially when the TOC information is to be recorded, the writeoperation is performed by moving a recording/playback head mechanismfrom the video recording area for recording video data to the systemmanagement area in a remote position. Hence, if the battery amountremains to such an extent that a video data recording operation ismarginally possible, the TOC information cannot be written in the worstcase.

If the TOC information is missing, the start pointer, end pointer,attribution, and the like of recorded video data are unknown, so diskmedium playback control cannot be performed.

Also, even if the reliability of the TOC data is improved as describedpreviously, recording is sometimes abnormally terminated in the middleof a scene by, e.g., careless handling by a user, running out or abruptdischarge of a battery, a defect of a recording medium, or some externalcause. In a case like this, actually recorded images and sounds andadditional data sometimes disagree with the contents of the TOC. Thismakes playback of the scene based on the TOC impossible.

SUMMARY OF THE INVENTION

It is an object of the present invention to solve the above conventionalproblems.

It is another object of the present invention to reliably recordmanagement information such as TOC information on a recording mediumwithout losing the management information, even when the remainingbattery amount becomes insufficient during image pickup recording.

It is still another object of the present invention to normallyreproduce a recorded signal halfway even when recording of the signal isnot normally completed.

To achieve the above objects, according to one aspect of the presentinvention, there is provided a recording apparatus comprisingreproducing means for reproducing management information pertaining to arecording address of an image signal from a disk-like recording mediumhaving a first area for the image signal and a second area for themanagement information, control means for detecting the state of thereproduced management information by using the management informationand, on the basis of the detection result, controlling the reproducingmeans to reproduce management data from the first area of the disk-likerecording medium, modifying means for modifying the managementinformation reproduced from the second area, on the basis of themanagement data reproduced from the first area, and recording means forrecording an image signal in the first area of the disk-like recordingmedium and recording the management information modified by themodifying means in the second area.

Other objects and features of the present invention will become apparentfrom the following detailed description of embodiments of the inventiontaken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the configuration of a recordingapparatus according to an embodiment of the present invention;

FIG. 2 is a block diagram showing the arrangement of a recording unitshown in FIG. 1;

FIG. 3 is a view showing the directory structure of the apparatus shownin FIG. 1;

FIG. 4 is a view showing a TOC processed by the apparatus shown in FIG.1;

FIG. 5 is a view showing the major components of an electric power unitof the apparatus shown in FIG. 1;

FIG. 6 is a flow chart for explaining an operation of the apparatusshown in FIG. 1;

FIG. 7 is a view showing another example of the TOC processed by theapparatus shown in FIG. 1;

FIG. 8 is a flow chart for explaining another operation of the apparatusshown in FIG. 1;

FIG. 9 is a view showing a recording format on a disk in the apparatusshown in FIG. 1;

FIG. 10 is a block diagram showing the configuration of a recordingapparatus according to another embodiment of the present invention;

FIG. 11 is a view for explaining picture rearrangement by the apparatusshown in FIG. 10;

FIG. 12 is a view for explaining encoding by the apparatus shown in FIG.10;

FIG. 13 is a timing chart showing the recording timings of TOC data inthe apparatus shown in FIG. 1;

FIG. 14 is a timing chart showing the recording timings of an imagesignal in the apparatus shown in FIG. 10;

FIGS. 15A and 15B are graphs showing a picture change detection processby the apparatus shown in FIG. 14;

FIG. 16 is a block diagram showing the configuration of a recordingapparatus according to still another embodiment of the presentinvention;

FIG. 17 is a graph for explaining the operation of an audio changedetection circuit of the apparatus shown in FIG. 16;

FIG. 18 is a timing chart showing the recording timings of TOC data inthe apparatus shown in FIG. 16;

FIG. 19 is a block diagram showing the configuration of a recordingapparatus according to still another embodiment of the presentinvention;

FIG. 20 is a view showing a recording format on a disk in the apparatusshown in FIG. 19;

FIG. 21 is a view showing recorded data on the disk shown in FIG. 20;and

FIG. 22 is a view showing TOC data processed by the apparatus shown inFIG. 21.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will be described indetail below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of arecording/playback apparatus 100 according to the first embodiment ofthe present invention. Referring to FIG. 1, this recording/playbackapparatus 100 comprises an optical system 101 including, e.g., a lensand a lens controller, an image pickup processing unit 102, an A/Dconverter 103, a camera signal processing unit 104, a video signalprocessing unit 105, a D/A converter 106, an analog video signal outputunit 107, a display unit 108, a data bus 109, a memory 110, a memorycontroller 111, a CPU 112, a disk unit 113, an electric power unit 114such as a battery, and an operation unit 115 including, e.g., a powerswitch and a recording trigger switch. For the sake of simplicity, theelectric power unit 114 is connected only to the CPU 112 in FIG. 1. Inreality, however, electric power is supplied to all units requiringpower via power lines.

In this recording/playback apparatus 100, the optical system 101including a lens performs iris control, focusing control, zoom control,and the like. The image pickup processing unit 102 photoelectricallyconverts an object image (not shown) by a CCD (Charge-Coupled Device) orthe like. The A/D converter 103 converts the obtained analog imagesignal into a digital signal. The camera signal processing unit 104performs predetermined data processing such as gamma correction andwhite balance adjustment for the digital image data.

In recording operation, the video signal processing unit 105 segmentsthe output image data from the camera signal processing unit 104 into aplurality of blocks each composed of a plurality of pixels, performsorthogonal transformation such as DCT for each block, and quantizes andencodes the blocks. Generally, a change between two continuous frames issmall in motion image data, so an image of interest has highcorrelations with images before and after that image. By using thischaracteristic, the differences between an image of interest and imagesof frames before and after the image of interest are encoded to performimage compression. An MPEG scheme is used most frequently by which thedifference between images is obtained after motion compensation isperformed to reduce the redundancy in the time axis, and orthogonaltransformation such as DCT and variable-length coding are performed onthe obtained differential data.

The image data compressed and encoded by the video signal processingunit 105 is output to the disk unit 113 and recorded on a magnetoopticaldisk, as will be described later.

In playback operation, image data reproduced by the disk unit 113 isoutput to the video signal processing unit 105. The video signalprocessing unit 105 performs decoding, which is the reverse of encodingperformed during recording, for the reproduced image data to expand itsinformation amount, and outputs the decoded data to the D/A converter106.

The D/A converter 106 converts the output digital video signal from thevideo signal processing unit 105 into an analog signal. The video signaloutput unit 107 converts this analog signal into a signal following atelevision system, such as NTSC or PAL, and outputs the signal. Thedisplay unit 108 is, e.g., a viewfinder or a liquid crystal monitor andallows a user to monitor an image currently being picked up, or areproduced image, on the basis of the output analog video signal fromthe D/A converter 106.

The CPU 112 controls the operation of the whole recording/playbackapparatus 100 via the data bus 109. The CPU 112 also controls parametersin the image pickup processing unit 102, the camera signal processingunit 104, and the video signal processing unit 105. The memory controlunit 111 controls data write to and read from the memory 110 inaccordance with a control signal from the CPU 112.

The arrangement of the disk unit 113 will be described below withreference to FIG. 2.

FIG. 2 is a block diagram showing the arrangement of the disk unit 113.

Referring to FIG. 2, this disk unit 113 includes a magnetooptical disk201, a magnetic head 202, a driver 203 of the magnetic head, an opticalpickup 214, and a preamplifier 205.

A disk motor 208 rotates the disk 201. A thread mechanism 210 moves themagnetic head 202 and the optical pickup 214 in the radial direction ofthe disk.

In recording operation, this optical pickup 214 irradiates the disk 201with a laser beam emitted from a semiconductor laser element (not shown)such as a laser diode. At the same time, an encoder 204 performs errorcorrection encoding and channel encoding such as digital modulation forvideo data input via an interface 207. The driver 203 drives themagnetic head 202 with a driving signal modulated on the basis of thedata processed by the encoder 204. In accordance with this modulateddriving signal, the magnetic head 202 records the data by performingmagnetic field modulation on the disk 201.

In playback operation, the pickup 214 irradiates the disk 201 with alaser beam emitted from the semiconductor laser element (not shown),detects the polarized light amount of reflected light caused by themagnetic Kerr effect, and supplies the detected amount to thepreamplifier 205. The output signal from the preamplifier 205 issubjected to demodulation and error correction decoding by a decoder206, and output to the video signal processing unit 105 shown in FIG. 1via the interface 207.

A DC motor 211 drives the thread mechanism 210. A servo digital signalprocessor (DSP) 213 controls the rotational speed of the disk and servooperations of the thread mechanism 210 by using a motor driver 209 and aservo driver 212. More specifically, the servo DSP 213 controls, e.g.,rotational servo of the disk and focusing servo, tracking servo, andseek servo of the pickup system.

The bus I/F 207 exchanges recording/playback data with the data bus 109shown in FIG. 1. That is, the bus I/F 207 controls input and output ofdata with respect to the encoder 204 during recording and controls inputand output of data with respect to the decoder 206 during playback.

A file (TOC data) structure used in this embodiment will be describedbelow.

First, TOC data processing by the CPU 112 will be explained.

In this embodiment, as shown in FIG. 9, an inner peripheral portion 901of a disk is used as a system management area, and TOC data is recordedin this system management area 901. Video and audio data are recorded ina video recording area 902.

The CPU 112 writes TOC data, which is read out from a disk by the diskunit 113, into the memory 110 via the memory control unit 111. In thisstate, the CPU 112 updates the TOC data stored in the memory 110 inaccordance with a recording or playback operation. When recording isstopped by the recording trigger switch or when the disk is to beejected, the CPU 112 records the TOC data in the system management area901.

FIG. 3 shows the file directory structure of the recording/playbackapparatus 100. Referring to FIG. 3, a disk medium 301 is defined asuppermost hierarchy 0. In lower hierarchy 1, application attributionssuch as video 302, audio 303, a still image 304, . . . , can beclassified. In lower hierarchy 2 of any file (in FIG. 3, the video 302)defined in hierarchy 1, video A 305, video B 306, video C 307, . . . ,can be classified in accordance with the dates of image pickup.Subsequently, in lower hierarchy 3 of any file (in FIG. 3, the video A305) defined in hierarchy 2, scene 1 (308), scene 2 (309), scene 3(310), . . . , partitioned by ON/OFF of the trigger pointer can beclassified. Furthermore, in lower hierarchy 4 of any file (in FIG. 3,scene 1 (308)) defined in hierarchy 3, an image pickup start pointer 311(address information), an image pickup end pointer 312 (addressinformation), a link pointer 313 (address information) which allows jumpduring editing and playback, . . . , of scene 1 can be classified.

Details of the TOC of the recording/playback apparatus 100 having thisdirectory structure are shown in FIG. 4. FIG. 4 depicts the structure ofthe TOC. This structure is roughly classified into a TOC identificationheader portion containing all 0s or all 1s, system information, and amanagement information table portion. For each item, a start pointer401, an attribution 402, an end pointer 403, and a link pointer 404 canbe defined in units of a few bytes.

As an example, playback control of a file in directory hierarchy 3 shownin FIG. 3 will be explained with reference to FIG. 4.

First, playback is started from the address, indicated by a startpointer A of address 0001 in the management information table portion,of the video recording area on a disk medium. After the recorded data iscontinuously reproduced to an address indicated by an end pointer B, theoperation jumps to address AAAA indicated by a link pointer.Subsequently, playback is started from the address, indicated by a startpointer C, of the video recording area on the disk medium. When therecorded data is completely reproduced to an address indicated by an endpointer D, the playback is completed. Link pointer 0000 in address AAAAis an index indicating the end of playback. The playback of image dataof each scene is controlled on the basis of attribution information.

In this embodiment, as shown in FIG. 4, a U flag (Urgency Flag) is setin the attribution information 402 of the system information portion.This U flag is 1-bit digital information used to check whether a TOCrecorded in the system management area of a disk is the latest one. Theuse of this U flag will be described in detail later.

FIG. 5 is a view showing the arrangement of the electric power unit 114shown in FIG. 1. This electric power unit 114 includes a power reductiondetector and monitors and detects a decrease in electric power.Referring to FIG. 5, this electric power unit 114 comprises a battery501, DC-DC converters 502 and 503, resistors 504, 505, and 506 fordividing voltage, and comparators 508 and 509.

Electric power from the battery 501 is converted into a predeterminedvoltage by the DC-DC converter 502 and supplied to each circuit of therecording/playback apparatus 100. The DC-DC converter 503 and thesubsequent elements detect power reduction. That is, the output voltagefrom the DC-DC converter 503 is divided to obtain a first thresholdvalue (Th1) by the resistors 504 and 505 and a second threshold value(Th2) by the resistors 506 and 507. Note that Th1>Th2.

The comparator 508 compares the battery voltage 501 with Th1 and outputsa binary digital signal indicating the comparison result. On the basisof the output from this comparator 508, the CPU 112 instructs to displaya power reduction warning if the battery voltage is equal to or lowerthan Th1. The comparator 509 compares the battery voltage 501 with Th2and outputs a binary digital signal indicating the comparison result. Onthe basis of the output from this comparator 509, the CPU 112 instructsto shut down the power supply if the battery voltage is equal to orlower than Th2.

A control operation by the CPU 112 in this embodiment will be describedbelow with reference to FIG. 6. FIG. 6 is a flow chart for explainingrecording and playback of image data and TOC data performed by the CPU112.

First, after power-on in step S601, the CPU 112 causes the disk unit 113to read out TOC data from the system management area 901 on the disk 201and write the TOC data in the memory 111. In step S602, the CPU 112checks for the U flag of the TOC stored in the memory 111. In thisembodiment, if the U flag is “0”, this indicates that the TOC isnormally recorded in the system management area 901 of the disk 201 whenthe last image data is recorded; if the U flag is “1”, this indicatesthat the TOC is not normally recorded in the system management area 901of the disk 201 when the last image data is recorded.

If the U flag is “0” in step S602, the CPU 112 waits for a processinginstruction in steps S603 and S604. If the processing instruction isother than the start of recording, the CPU 112 performs correspondingprocessing in step S605.

If the instruction is the start of recording, in step S606 the CPU 112sets the U flag of the TOC data stored in the memory 111 to “1” whichindicates that the TOC has not been updated, and causes the disk unit113 to record the TOC data having this U flag “1” in the systemmanagement area 901 of the disk 201. After that, the CPU 112 performsrecording processing in step S607 and at the same time always checks forthe result of monitoring by the power reduction detector of the electricpower unit 114 in step S608.

If the CPU 112 detects in step S608 that the battery power lowers andthe voltage is below the predetermined voltage Th1, the flow advances tostep S612, and the CPU 112 stops recording the image. In accordance withthe recording stop position, in step S613 the CPU 112 updates thecontents of the TOC data stored in the memory 111, so as to reflect therecording start pointer, end pointer, and link pointer of the image datacurrently being recorded, thereby urgently recording the TOCinformation.

In step S613, unlike normal recording processing of TOC data, the TOCdata is written following the trailing end of the image data whoserecording into the video information recording area 902 is stopped,without moving the head mechanism of the disk unit 113 to the systemmanagement area 901. After performing this TOC data recording processingin step S613, the CPU 112 waits for the next instruction.

On the other hand, if the battery power is not low in step S608 and arecording stop instruction is detected in step S609, in step S610 theCPU 112 updates the contents of the TOC data stored in the memory 111,so as to reflect the start pointer, end pointer, and link pointer of thelatest recorded image data, and sets the U flag to “0”. In step S611,the CPU 112 moves the head mechanism to the system management area 901and writes the TOC information having the updated contents and the Uflag “0” in this system management area 901.

If in step S602 the U flag is set to “1” indicating that the TOC doesnot show the latest contents, the flow advances to step S614.

In this case, the TOC recorded in the system management area 901 has notbeen updated to the latest information. Therefore, the CPU 112sequentially searches the video recording area 902 of the disk 201 froma position indicated by the final end pointer of the latest TOCinformation recorded in the system management area 901, and reads outthe latest TOC information recorded in the video information recordingarea 902 as described previously. In step S615, on the basis of thereadout latest TOC information, the CPU 112 updates the contents of theTOC information stored in the memory 111 and sets the U flag to “0”. Instep S616, the CPU 112 records this TOC information in the systemmanagement area 901 which is the original recording area of TOCinformation.

The CPU 112 continues the above operation until power-off or until thebattery voltage becomes lower than Th2 and then the comparator 509 shownin FIG. 5 outputs a signal indicating a power-supply voltage drop.

In this embodiment as described above, even when the battery voltagelowers during recording, TOC information reflecting the latest recordedcontents can be reliably recorded.

The second embodiment will be described next. A recording/playbackapparatus of this embodiment has the same configuration as the imagepickup recording/playback apparatus explained with reference to FIGS. 1,2, and 5 in the first embodiment, so a detailed description thereof willbe omitted.

In the second embodiment, a TOC is constructed as shown in FIG. 7.One-bit remove information indicating that this TOC information is notnormally recorded and its contents do not reflect the latest recordedcontents can be described in the MSBs of attribution data 402′ in amanagement information table portion.

Processing by a CPU 112 in this embodiment will be described below withreference to a flow chart in FIG. 8.

First, after power-on in step S801, the CPU 112 causes a disk unit 113to read out TOC data from a system management area 901 on a disk 201 andwrite the TOC data in a memory 111. In step S802, the CPU 112 checks forall MSBs in the attributions 402′ of the TOC stored in the memory 111.In this embodiment, if the MSB of the attribution 402′ is “0”, thisindicates that the TOC is normally recorded in the system managementarea 901 of the disk 201 when the last image data is recorded; if theMSB is “1”, this indicates that the TOC is not normally recorded in thesystem management area 901 of the disk 201 when the last image data isrecorded and that the contents of this TOC do not correspond to thelatest recorded contents.

If the MSB of the attribution 402′ is “0” in step S802, the CPU 112waits for a processing instruction in steps S803 and S804. If theprocessing instruction is other than the start of recording, the CPU 112performs corresponding processing in step S805.

If the instruction is the start of recording, in step S806 the CPU 112sets the MSB of the attribution 402′ of the TOC data stored in thememory 111 to “1” which indicates that the TOC has not been updated, andcauses the disk unit 113 to record the TOC data having this MSB “1” ofthe attribution 402′ in the system management area 901 of the disk 201.After that, the CPU 112 performs recording processing in step S807 andat the same time always checks for the result of monitoring by a powerreduction detector of an electric power unit 114 in step S808.

If in step S808 the CPU 112 detects the battery supply limit, i.e.,detects that the battery voltage is below a predetermined voltage Th1,the flow advances to step S812, and the CPU 112 stops recording theimage. In accordance with this recording stop position, in step S813 theCPU 112 updates the contents of the TOC data stored in the memory 111,so as to reflect the recording start pointer, end pointer, and linkpointer of the image data currently being recorded, thereby urgentlyremoving the TOC information.

In step S813, unlike normal recording processing of TOC data, the TOCdata is written following the trailing end of the image data whoserecording into a video information recording area 902 is stopped,without moving a head mechanism of the disk unit 113 to the systemmanagement area 901. After performing this TOC data recording processingin step S813, the CPU 112 waits for the next instruction.

On the other hand, if the battery power is not low in step S808 and arecording stop instruction is detected in step S809, in step S810 theCPU 112 updates the contents of the TOC data stored in the memory 111,so as to reflect the start pointer, end pointer, and link pointer of thelatest recorded image data, and sets the MSB of the attribution 402′ to“0”. In step S811, the CPU 112 moves the head mechanism to the systemmanagement area 901 and writes the updated TOC information in thissystem management area 901.

If in step S802 the MSB of the attribution 402′ is set to “1” indicatingthat the TOC does not show the latest contents, the flow advances tostep S814.

In this case, the TOC recorded in the system management area 901 has notbeen updated to the latest information. Therefore, the CPU 112sequentially searches the video recording area 902 of the disk 201 froma position indicated by the final end pointer of the newest TOCinformation recorded in the system management area 901, and reads outthe latest TOC information recorded in the video information recordingarea 902 as described above. In step S815, on the basis of the readoutlatest TOC information, the CPU 112 updates the contents of the TOCinformation stored in the memory 111 and sets the MSB of the attribution402′ to “0”. In step S816, the CPU 112 records this TOC information inthe system management area 901 which is the original recording area ofTOC information.

The CPU 112 continues the above operation until power-off or until thebattery voltage becomes lower than Th2 and then a comparator 509 shownin FIG. 5 outputs a signal indicating a power-supply voltage drop.

In this embodiment as described above, even when the battery voltagelowers during recording, TOC information reflecting the latest recordedcontents can be reliably recorded and reproduced.

In the first and second embodiments, the present invention is applied tothe recording/playback apparatus 100. However, the present invention issimilarly applicable to any apparatus which separately records maininformation and its management information in separated areas on arecording medium.

The third embodiment of the present invention will be described belowwith reference the accompanying drawings.

FIG. 10 is a block diagram showing a recording apparatus 1000 accordingto this embodiment of the present invention.

This recording apparatus 1000 comprises an image pickup unit 1001, apicture rearrangement circuit 1002, a switch 1003, a subtractor 1004, aDCT (Discrete Cosine Transform) circuit 1005, a quantization circuit1006, a variable-length encoding circuit 1007, an inverse quantizationcircuit 1008, an IDCT (Inverse Discrete Cosine Transform) circuit 1009,an adder 1010, a motion compensation prediction circuit 1011, a switch1012, a buffer 1013, a rate control circuit 1014, a recording processingcircuit 1015, a magnetooptical disk 1016, a picture change detectioncircuit 1017, a TOC memory 1018 for storing TOC information, a TOCcontrol circuit 1019, and an operation unit 1020 which includes, e.g., apower switch and a recording trigger switch.

The operation will be described next.

A digital image signal obtained by the image pickup unit 1001 is inputin units of frames to the picture rearrangement circuit 1002. Thispicture rearrangement circuit 1002 has a memory capable of storing adigital image signal having a plurality of frames. By using this memory,the picture rearrangement circuit 1002 rearranges frames of the inputimage signal and outputs the signal.

The operation of the picture rearrangement circuit 1002 will beexplained below with reference to FIG. 11.

Referring to FIG. 11, an image signal input in units of frames in theorder of a first frame, second frame, third frame, . . . , is output byrearranging these frames in the order of the third frame, first frame,second frame, . . . .

The picture rearrangement process shown in FIG. 11 is necessary toperform intra-encoding and inter-encoding for an image signal as shownin FIG. 12.

The intra-encoding is a method of encoding using only data in one frameand generates an I picture shown in FIG. 12. The inter-encoding is amethod of encoding also using interframe prediction and generates P andB pictures shown in FIG. 12.

The intra-encoding and inter-encoding will be described next.

To perform the intra-encoding, the switch 1003 is closed to a terminalA. The output image data from the picture rearrangement circuit 1002 isinput to the DCT circuit 1005 via the switch 1003 and orthogonallytransformed. The quantization circuit 1006 quantizes the orthogonallytransformed image data in accordance with a quantization coefficientdetermined by the rate control circuit 1014. The quantized image data isinput to the inverse quantization circuit 1008 and the variable-lengthencoding circuit 1007.

The output image data from the picture rearrangement circuit 1002 isalso input to the motion compensation prediction circuit 1011 and thepicture change detection circuit 1017.

The quantized data is inversely quantized by the inverse quantizationcircuit 1008 and subjected to IDCT by the IDCT circuit 1009. The switch1012 is turned off to supply the image data subjected to IDCT to themotion compensation prediction circuit 1011. The motion compensationprediction circuit 1011 generates and outputs a predictive image for thesubsequent inter-encoding.

The quantized data is also input to the variable-length encoding circuit1007 where the data is variable-length-encoded. The encoded data isinput to the buffer 1013. When reaching a certain predetermined dataamount, the image data in the buffer 1013 is output to the recordingprocessing circuit 1015. This recording processing circuit 1015 has anarrangement as shown in FIG. 2 and records the data on themagnetooptical disk 1016. The recording processing circuit 1015 canrecord data at a higher data rate than the rate of image data input tothe buffer 1013. In practice, the recording processing circuit 1015intermittently reads out data in units of predetermined amounts of datafrom the buffer 1013 and records the readout data.

To perform the inter-encoding, the switch 1003 is closed to a terminalB. The subtractor 1004 is used to lower the redundancy in the time axis.This subtractor 1004 outputs the difference between the output imagedata from the picture rearrangement circuit 1002 and the predictiveimage data from the motion compensation prediction circuit 1011 to theterminal B of the switch 1003.

The output data from the subtractor 1004 is input to the DCT circuit1005 via the switch 1003 and orthogonally transformed. The quantizationcircuit 1006 quantizes the orthogonally transformed image data inaccordance with a quantization coefficient determined by the ratecontrol circuit 1014. The quantized image data is input to the inversequantization circuit 1008 and the variable-length encoding circuit 1007.

The output image data from the picture rearrangement circuit 1002 isalso input to the motion compensation prediction circuit 1011 and thepicture change detection circuit 1017.

The quantized data is inversely quantized by the inverse quantizationcircuit 1008 and subjected to IDCT by the IDCT circuit 1009. In thisinter-encoding, the switch 114 is turned on to allow the adder 1010 toadd the image data from the IDCT circuit 1009 and the predictive imagedata from the motion compensation prediction circuit 1011, therebyobtaining decoded image data. This decoded image data is input to themotion compensation prediction circuit 1011 for the subsequent imageencoding. The motion compensation prediction circuit 1011 outputspredictive image data and a motion vector. This motion vector is inputto the variable-length encoding circuit 1007.

The quantized data is input to the variable-length encoding circuit 1007where the data is variable-length-encoded. The encoded data is input tothe buffer 1013. When reaching a certain predetermined data amount, theimage data in the buffer 1013 is output to the recording processingcircuit 1015. The recording processing circuit 1015 records the imagedata on the disk 1016.

Recording of a TOC as index information in this embodiment will bedescribed below.

Also in this embodiment, TOC information is recorded in a systemmanagement area 901 on a disk shown in FIG. 9.

When the power supply is turned on by the operation unit 1020, the TOCcontrol circuit 1019 stores TOC information, read out from the systemmanagement area on the disk 1016 by the recording processing circuit1015, in the TOC memory 1018. In accordance with recording processing,the TOC control circuit 1019 updates the contents of the TOC informationstored in the TOC memory 1018. When the stop of recording is designatedby the operation unit 1020, the TOC control circuit 1019 reads out thelatest TOC information stored in the TOC memory 1018. The recordingprocessing circuit 1015 records the readout TOC information in thesystem management area of the disk 1016.

Furthermore, the TOC control circuit 1019 records the TOC informationstored in the TOC memory 1018 into the disk 1016 in accordance with anoutput from the picture change detection circuit 1017.

This picture change detection circuit 1017 reads out image data of aplurality of frames stored in the picture rearrangement circuit 1002 andcalculates a difference AA=∫|Frame1(Y)−Frame2(Y)|  (1)in luminance information between frames. If this difference A is largerthan a certain threshold value TH, i.e., if A>TH, the picture changedetection circuit 1017 outputs a control signal indicating a picturechange to the TOC control circuit 1019.

When detecting this control signal, the TOC control circuit 1019controls the TOC memory 1018 to record TOC information which reflectsthe contents of recording up to the point, in the system management areaof the disk 1016 by the recording processing circuit 1015, by using aperiod during which no image data is recorded.

FIGS. 13 and 14 are views for explaining TOC recording timings.

Symbols ★ in FIG. 13 indicate timings at which the picture changedetection circuit 1017 detects a large picture change.

Referring to FIG. 13, in scene 1, TOC information is recorded in thesystem management area at the timings of detection of picture change1301, temporary stop 1302, and stop of recording 1303.

As described earlier, image data is output to the recording processingcircuit 1015 via the buffer 1013. Also, the recording processing circuit1015 can record data on the disk 1016 at a higher rate than the datarate of image data input to the buffer 1013.

That is, the recording processing circuit 1015 performs intermittentrecording on the disk 1016. As shown in FIG. 14, therefore, non-recordperiods are produced during recording of image data. FIG. 14 showsrecording periods 1401 and data non-record periods 1402. Accordingly,when a picture change is detected at timing 1401 a, TOC information canbe recorded, even during image data recording, by moving the head to thesystem management area in a data non-record period 1402 a.

Also, in scene 1 of FIG. 13, recording is normally stopped at timing1303. Hence, TOC information reflecting data recorded up to this stop ofrecording 1303 is recorded in the disk 1016. So, all recorded data up to1303 can be correctly reproduced.

In scene 2, TOC information is recorded in the system management area atpicture change detection timings 1304 and 1305. In this example, thepower supply is shut down at timing 1306 before recording stopoperation, so recording is not normally stopped. However, TOCinformation is recorded on the disk 1016 at the timing 1305 at which apicture change is detected. The TOC information recorded at this timing1305 reflects the contents of image data recorded up to 1305. Inplayback, therefore, data from the start of recording of scene 2 to thetiming 1305 at which a picture change is lastly detected can becorrectly reproduced.

In this embodiment, a picture change is detected by the differencebetween frames. However, a picture change can also be detected byanother method.

For example, as shown in FIGS. 15A and 15B, a histogram of thedirections of motion vectors calculated by the motion compensationprediction circuit 113 is obtained in one frame. If the correlationbetween the motion vectors in one frame is low, a picture change isdetected.

Referring to FIG. 15A, motion vectors having angles of 0 to 90° islargest in number, so changes between pictures are obviously small.Referring to FIG. 15B, the angles of motion vectors evenly distribute inall directions, so changes between pictures are obviously large.

A recording apparatus according to the fourth embodiment of the presentinvention will be described below.

FIG. 16 is a block diagram showing the configuration of a recordingapparatus 1000 of this embodiment. The same reference numerals as in theconfiguration shown in FIG. 10 denote the same parts, and a detaileddescription thereof will be omitted.

This apparatus shown in FIG. 16 includes an audio input unit 1021, anaudio change detection circuit 1022, an audio encoding circuit 1023, abuffer 1024, and a multiplexer 1025.

Encoding of image data in FIG. 16 is the same as the apparatus shown inFIG. 10, so a detailed description thereof will be omitted. Encodedimage data stored in the buffer 1013 is multiplexed with audio data bythe multiplexer 1025 and output to a recording processing circuit 1015.

The audio input unit 1021 includes an audio input device such as amicrophone and outputs a digital audio signal pertaining to an object tothe audio change detection circuit 1022 and the audio encoding circuit1023. The audio encoding circuit 1023 encodes this audio data by using aknown coding scheme and outputs the encoded image data to the buffer1024. The multiplexer 1025 multiplexes the image data stored in thebuffer 1013 and the audio data stored in the buffer 1024 such thatpictures and audio are synchronized. The multiplexed data is output tothe recording processing circuit 1015.

Recording of a TOC as an important point of the present invention willbe described next.

Also in this embodiment, TOC information is recorded in a systemmanagement area 901 on a disk shown in FIG. 9.

When the power supply is turned on by an operation unit 1020, a TOCcontrol circuit 1019 stores TOC information read out from the systemmanagement area on a disk 1016 by the recording processing circuit 1015,in a TOC memory 1018. In accordance with recording processing, the TOCcontrol circuit 1019 updates the contents of the TOC information storedin the TOC memory 1018. When the stop of recording is designated by theoperation unit 1020, the TOC control circuit 1019 reads out the newestTOC information stored in the TOC memory 1018. The recording processingcircuit 1015 records the readout TOC information in the systemmanagement area of the disk 1016.

In this embodiment, the TOC control circuit 1019 further records the TOCinformation stored in the TOC memory 1018 into the disk 1016 inaccordance with an output from the audio change detection circuit 1022.

This audio change detection circuit 1022 has a comparator and, as shownin FIG. 17, outputs a high-level signal to the TOC control circuit 1019when a period during which the level of an input audio signal is lowerthan a predetermined threshold Ath continues for a predetermined timeTth or more. When the audio change detection circuit 1022 outputs thishigh-level control signal, the TOC control circuit 1019 controls the TOCmemory 1018 to record TOC information which reflects the contents ofrecording up to the point, in the system management area of the disk1016 by the recording processing circuit 1015, by using a period duringwhich neither image data nor audio data are recorded.

FIG. 18 is a view for explaining TOC recording timings.

Symbols

in FIG. 18 indicate timings at which the audio change detection circuit1022 outputs a control signal indicating that a period in which theinput audio level is lower than the threshold value is detected. Inscene 1, TOC information is recorded in the system management area 901of the disk 1016 at the timings of audio change detection 1801,temporary stop 1802, and stop of recording 1803.

Also in this embodiment, image data is output to the recordingprocessing circuit 1015 via a buffer 1013. Also, the recordingprocessing circuit 1015 can record data on the disk 1016 at a higherrate than the data rate of image data input to the buffer 1013.

That is, the recording processing circuit 1015 performs intermittentrecording on the disk 1016. As shown in FIG. 14, therefore, non-recordperiods are produced during recording of image data. FIG. 14 showsrecording periods 1401 and data non-record periods 1402. Accordingly,when a picture change is detected at timing 1401 a, TOC information canbe recorded, even during image data recording, by moving the head to thesystem management area 901 in a data non-record period 1402 a.

Also, in scene 1 of FIG. 18, recording is normally stopped at timing1803. Hence, TOC information reflecting data recorded up to this stop ofrecording 1803 is recorded in the disk 1016. So, all recorded data up to1803 can be correctly reproduced.

In scene 2, TOC information can be recorded in the system managementarea on the disk 1016 at audio change detection timings 1804 and 1805.In this example, the power supply is shut down at timing 1806 beforerecording stop operation, so recording is not normally stopped.

In this embodiment, however, TOC information reflecting the contents ofrecording up to the point is recorded on the disk 1016 at the timing1805 at which an audio change is detected. Therefore, data from thestart of recording of scene 2 to the timing 1805 at which an audiochange is lastly detected can be correctly reproduced.

The fifth embodiment of the present invention will be described belowwith reference to the accompanying drawings.

FIG. 19 is a block diagram showing the configuration of a recordingapparatus 1000 according to this embodiment. The same reference numeralsas in the configurations shown in FIGS. 10 and 16 denote the same parts,and a detailed description thereof will be omitted.

The recording apparatus of this embodiment further comprises a systemcontrol circuit 1026 for controlling the overall operation of theapparatus 1000, a still image encoding circuit 1027, a buffer 1028 forstill image signals, and a buffer 1029 for TOC information.

Referring to FIG. 19, the system control circuit 1026 controls theoperation of each unit of the apparatus. That is, in accordance withinstructions from an operation unit 1020, the system control circuit1026 controls a picture rearrangement circuit 1002, switches 1003 and1012, and the still image encoding circuit 1027.

First, the operation of normal motion image recording will be describedbelow.

When the start of motion image recording is designated by the operationunit 1020, the system control circuit 1026 controls a picturerearrangement circuit 1022 to rearrange frames of an image signal froman image pickup unit 1001 as shown in FIG. 11, and outputs the signal toa switch 1003, a subtractor 1004 and a motion compensation predictioncircuit 1011. After that, this motion image signal is encoded asdescribed earlier by, e.g., a DCT circuit 1005, a quantization circuit1006, a variable-length encoding circuit 1007, an inverse quantizationcircuit 1008, an IDCT circuit 1009, an adder 1010, and the motioncompensation prediction circuit 1011. The encoded signal is output to abuffer 1013.

Also, an input audio signal from an audio input unit 1021 is encoded byan audio encoding circuit 1023 and output to a buffer 1024.

The operation of still image recording will be described next.

The recording apparatus of this embodiment has a still image recordingmode. When still image recording is designated by the operation unit1020 during recording of a motion image signal, a still image signal canbe recorded on a disk 1016 independently of the motion image signal.

When the operation unit 1020 designates still image recording, thesystem control circuit 1026 outputs a control signal to the picturerearrangement circuit 1022 to extract image data of a frame, at thetiming corresponding to the still image recording instruction, from animage signal having a plurality of frames output from the image pickupunit 1001. The extracted image signal is output to the still imageencoding circuit 1027.

In accordance with a control signal from the system control circuit1026, the still image encoding circuit 1027 receives the image data ofone frame output from the picture rearrangement circuit 1002, encodesthe data on the basis of a JPEG standard for still image encoding, andoutputs the encoded still image data to the buffer 1028. The encodingscheme of this still image encoding circuit 107 is, of course, notlimited to JPEG encoding. For example, base band encoding can also beperformed. The still image encoding circuit 1027 performs real-timeprocessing at a rate of, e.g., 4 Mbits/sec.

Under the control of the system control circuit 1026, a multiplexer 1025time-divisionally multiplexes the motion image signal and audio signalstored in the buffer 1024, the still image signal stored in the buffer1028, and TOC information stored in the buffer 1029 (as will bedescribed later), and outputs the multiplexed data to a recordingprocessing unit 1015. The recording processing unit 1015 records thismultiplexed data in the magnetooptical disk 1016.

FIG. 20 is a view showing recording areas of TOC data, motion imageaudio data, and still image data on the disk 1016 according to thisembodiment.

Referring to FIG. 20, TOC data is recorded in a TOC recording area 901in the innermost peripheral portion as in FIG. 9. In this embodiment, avideo recording area is divided into a motion image recording area 902Aand a still image recording area 902B. That is, still image data isrecorded in the still image recording area 902B outside the TOCrecording area 901. Motion image audio data is recorded in the motionimage audio recording area 902A outside the still image recording area902B.

The still image recording area 902B and the motion image audio recordingarea 902A are segmented into sectors toward the outer periphery, andthese sectors are assigned sector numbers in order. Each sector isreferred to by the start address, end address, and the like in TOC data.

As shown in FIG. 21, the recording processing circuit 1015 recordsvariable-length motion image data in units of GOP and fixed-length audiodata in a time series manner in the motion image recording area 902A onthe disk 1016. In encoding of MPEG2, a plurality of frames between two Ipictures are called 1GOP (Group Of Pictures) and used as a unit ofencoding. Usually, 1GOP is composed of 15 frames.

When still image data is stored in the buffer 1028 in response to astill image recording instruction, the system control circuit 1026controls the multiplexer 1025 to read out this still image data storedin the buffer 1028 by using a period during which recording of motionimage data and audio data on the disk 1016 is stopped, i.e., a period1401 shown in FIG. 14. The readout still image data is recorded in thestill image recording area 902B different from the motion imagerecording area 902A on the disk 1016.

TOC data in this embodiment will be described below.

FIG. 22 is a view showing the contents of TOC data according to thisembodiment.

The TOC of this embodiment has a scene table 2201 and a contents table2202. The scene table 2201 shows the order of scenes and thecorrespondence between each scene and a row in the contents table 2202.In playback, scenes are usually reproduced in the order in this scenetable 2201.

Also, the scene table 2201 can manage 4,095 scenes, and each scene has a12-bit pointer which indicates a specific row in the contents table2202. This scene table 2201 is used in order from 1, and a pointerhaving no corresponding scene has “0” which indicates the end.

The contents table 2202 has 4,095 rows, and each row has a start address2203, an end address 2204, a link pointer 2205, and an attribution 2206.The start address 2203 and the end address 2204 are composed of 20 bitseach and have the start and end addresses, respectively, of acorresponding scene.

The link pointer 2205 has a pointer indicating the row of thecontinuation of a scene, when a certain scene is connected to anotherscene to form one scene or when one scene is dispersedly recorded indiscontinuous areas owing to the locations of empty areas. As indicatedby an arrow in FIG. 22, when the continuation of a scene shown in row 1of the contents table 2202 is shown in row 3, “3” is stored in the linkpointer 2205 of row 1 to hold the continuity of the scene.

The attribution 2206 stores data indicating an attribution such asmotion image, still image, or copy inhibition.

Data to be processed is, of course, not restricted to motion image audiodata and still image data but can be script data and the like. The typeof data can be described in the attribution 2206 of the TOC data.

A summary of updating of TOC data as management information in thepresent invention will be explained below. Details will be describedlater.

When the power supply is turned on, only TOC data is reproduced from theTOC recording area 901 on a recording medium and stored in the TOCmemory 1018. The system control circuit 1026 can instantly know whichdata is stored in which area on the disk 1016 at present by referring tothe TOC data loaded into the TOC memory 1018. To record a motion imageand a still image, therefore, the system control circuit 1026 socontrols as to record new data by designating an empty area on the basisof the TOC.

In this embodiment, whenever the operation unit 1020 designates stillimage recording, the system control circuit 1026 updates the TOC datastored in the TOC memory 1018 to have contents recorded up to thatpoint, i.e., to have contents reflecting all pieces of informationconcerning motion image data recorded up to that point and still imagedata to be recorded henceforth.

The system control circuit 1026 outputs the TOC data having the updatedcontents to the buffer 1029 and records the still image data, stored inthe buffer 1028, into the still image recording area 902B on the disk atthe aforementioned timing. Subsequently, the system control circuit 1026reads out the TOC data stored in the buffer 1029 and records the readoutTOC data in the system management area 901 on the disk 1016. Also inthis embodiment, whenever the operation unit 1020 designates the startand end of normal motion image recording, the system control circuit1026 updates the contents of the TOC data, supplies the updated TOC datafrom the TOC memory 1018 to the buffer 1029, and records the TOC data inthe system management area 901 on the disk 1016.

Still image recording can be designated even while no motion image isbeing recorded. Also in this case, TOC data is updated and recorded onthe disk 1016.

In this embodiment as described above, when recording of a still imageis instructed while a motion image is being recorded, TOC datareflecting recorded contents is recorded on a disk at that time.

During image pickup of one scene, therefore, even when abnormality suchas a decrease in remaining battery amount occurs and recording of amotion image is not normally terminated, if still image recording isdesignated at least once while a motion image is being picked up, TOCdata reflecting recorded contents up to that point the still image datais recorded can be recorded on a disk.

Accordingly, the motion image data, audio data, and still image datarecorded up to that point can be correctly reproduced.

The present invention can be applied to a system constituted by aplurality of devices or an apparatus comprising a single device.

Further, the objects of the present invention can also be achieved bysupplying a storage medium (or a recording medium) recording programcodes of software for realizing the functions of the abovementionedembodiments to a system or an apparatus, and allowing a computer (e.g.,a CPU or MPU) of the system or the apparatus to read out and execute theprogram codes stored in the storage medium. In this case, the programcodes themselves read out from the storage medium realize the functionsof the above embodiments, and the storage medium storing the programcodes constitutes the invention. Furthermore, besides the functions ofthe above embodiments are realized by executing readout program codes bya computer, the present invention includes a case where an OS (OperatingSystem) or the like running on the computer executes a part or the wholeof actual processing on the basis of instructions by the program codes,and the functions of the embodiments are achieved by the processing.

The present invention also includes a case where, after the programcodes read out from the storage medium are written in a memory of afunction extension board inserted into a computer or of a functionextension unit connected to the computer, a CPU or the like of thefunction extension board or function extension unit performs a part orthe whole of actual processing on the basis of instructions by theprogram codes, and the functions of the above embodiments areaccomplished by the processing.

Many widely different embodiments of the present invention may beconstructed without departing from the spirit and scope of the presentinvention. It should be understood that the present invention is notlimited to the specific embodiments described in the specification,except as defined in the appended claims.

What is claimed is:
 1. A recording apparatus comprising: a recordingunit that records in a recording medium moving image data and amanagement information concerning the moving image data recorded in therecording medium, the management information having an attributeinformation of the moving image data, the moving image data recorded inthe recoding medium being reproduced in accordance with the attributeinformation; a CPU that controls the recording unit so as to record themoving image data in the recording medium in accordance with a recordingstart instruction and to stop recording the moving image data inaccordance with a recording stop instruction, wherein the CPU generatesthe management information in accordance with the recording operation ofthe moving image data by the recording unit; wherein the CPU controlsthe recording unit, in accordance with the recording start instruction,to record the management information having the attribute informationhaving a predetermined value indicating that the management informationis not updated, and wherein the CPU controls the recording unit, inaccordance with the recording stop instruction, to update managementinformation recorded in the recording medium such that the managementinformation recorded in the recording medium has the attributeinformation having a value different from the predetermined value.
 2. Anapparatus according to claim 1, wherein the management information hasinformation indicating positions where the moving image data arerecorded in the recording medium.
 3. An apparatus according to claim 1,wherein the CPU checks the attribute information in the managementinformation recorded in the recording medium, and wherein if it isdetected that the attribute information recorded in the recording mediumhas the predetermined value, the CPU updates the management informationin accordance with an information recorded in the recording medium. 4.An apparatus according to claim 1, further comprising: a power supplyunit, wherein if a decrease in electric power from the power supply unitis detected during recording of the moving image data, the CPU controlsthe recording unit so as to stop recording the moving image data withoutchanging the value of the attribute information in the managementinformation.
 5. An apparatus according to claim 1, further comprising:an image pickup unit, wherein the recording unit records the movingimage data obtained by the image pickup unit.
 6. A recording apparatuscomprising: a CPU; a recording unit that records in a recording mediummoving image data and a management information concerning the movingimage data recorded in the recording medium having a recording area forthe management information, the recording unit recording the managementinformation in the recording area for the management information; agenerating unit that generates the management information in accordancewith the recording operation of the moving image data by the recordingunit; and a memory that stores the management information generated bythe generation unit; a controller that controls the recording unit so asto record the moving image data in the recording medium in accordancewith a recording start instruction and to stop recording the movingimage data in accordance with a recording stop instruction; a powersupply unit, wherein the controller controls the generating unit and therecording unit such that in accordance with the recording startinstruction, a predetermined portion of the management information isset to a predetermined value representing that the managementinformation is not updated and the management information having thepredetermined portion set to the predetermined value is recorded in therecording area for the management information, wherein the controllercontrols the generation unit and the recording unit in accordance withthe recording stop instruction, to update the management informationrecorded in the recording area for the management information such thatthe predetermined portion of the management information recorded in therecording medium has a different value from the predetermined value, andwherein if a decrease in electric power from the power supply unit isdetected during recording of the moving image data, the controllercontrols the recording unit so as to stop recording the moving imagedata without updating the management information recorded in therecording area for the management information and record the managementinformation stored in the memory in a recording area of the recordingmedium other than the recording area for the management information,wherein the generating unit and the controller are implemented by theCPU.
 7. An apparatus according to claim 6, wherein the managementinformation indicates positions where the moving image data are recordedin the recording medium.
 8. An apparatus according to claim 6, whereinthe control unit checks the predetermined portion of the managementinformation recorded in the recording medium, and wherein if thepredetermined portion of the management information recorded in therecording medium is set to the predetermined value, the recording areafor the management information in accordance with the managementinformation recorded in the other recording area.
 9. An apparatusaccording to claim 6, further comprising: an image pickup unit, whereinthe recording unit records the moving image data obtained by the imagepickup unit.